Catalyst and method of manufacture

Abstract

A catalyst system comprising a first catalytic composition comprising a first catalytic material disposed on a metal inorganic support; wherein the metal inorganic support has pores; and at least one promoting metal. The catalyst system further comprises a second catalytic composition comprising, (i) a zeolite, or (ii) a first catalytic material disposed on a first substrate, the first catalytic material comprising an element selected from the group consisting of tungsten, titanium, and vanadium. The catalyst system may further comprise a third catalytic composition. The catalyst system may further comprise a delivery system configured to deliver a reductant and optionally a co-reductant. A catalyst system comprising a first catalytic composition, the second catalytic composition, and the third catalytic composition is also provided. An exhaust system comprising the catalyst systems described herein is also provided.

The invention claimed is: 
     
       1. A catalyst system comprising:
 a first catalytic composition comprising a homogeneous solid mixture containing at least one catalytic metal and at least one metal inorganic support wherein pores of the solid mixture have an average diameter of about 1 nanometer to about 15 nanometers; and at least one promoting metal; and 
 a second catalytic composition comprising (i) a zeolite or (ii) a first catalytic material disposed on a first substrate, 
 the first catalytic material comprising an element selected from the group consisting of tungsten, titanium, and vanadium, 
 wherein prior to combining the homogenous solid mixture with the second catalytic composition, the homogeneous solid mixture is prepared by mixing a precursor of the metal inorganic support, a templating agent, and a precursor of the catalytic metal and calcining the resulting mixture. 
 
     
     
       2. The catalyst system of  claim 1 , wherein the catalytic metal comprises alkali metals, alkaline earth metals, transition metals, or a combination thereof. 
     
     
       3. The catalyst system of  claim 1 , wherein the catalytic metal comprises silver, platinum, gold, palladium, iron, nickel, cobalt, gallium, indium, ruthenium, rhodium, osmium, iridium, or combinations of at least two of the foregoing metals. 
     
     
       4. The catalyst system of  claim 1 , wherein the catalytic metal comprises silver. 
     
     
       5. The catalyst system of  claim 1 , wherein the metal inorganic support comprises alumina. 
     
     
       6. The catalyst system of  claim 1 , wherein the at least one promoting metal is selected from the group consisting of gallium, indium, gold, vanadium, zinc, tin, bismuth, cobalt, molybdenum, and tungsten. 
     
     
       7. The catalyst system of  claim 1 , wherein the zeolite comprises zeolite Y, zeolite beta, mordenite, ferrierite, ZSM-5, ZSM-12, ZSM-22, ZSM-23, ZSM-34, ZSM-35, ZSM-38, ZSM-48, ZSM-50, ZSM-57, zeolite A, zeolite X, or a combination comprising at least two of the foregoing zeolites. 
     
     
       8. The catalyst system of  claim 1 , wherein the zeolite comprises zeolite Y, zeolite beta, mordenite, ferrierite, ZSM-5, or a combination comprising at least two of the foregoing zeolites. 
     
     
       9. The catalyst system of  claim 1 , wherein the first substrate comprises at least one member selected from the group consisting of alumina, titania, zirconia, ceria, silicon carbide and mixtures thereof. 
     
     
       10. The catalyst system of  claim 1 , further comprising a third catalytic composition disposed downstream from the second catalytic composition; the third catalytic composition comprising a second catalytic material disposed on a second substrate, wherein the second catalytic material is selected from the group consisting of platinum, palladium, ruthenium, rhodium, osmium, and iridium. 
     
     
       11. The catalyst system of  claim 10 , wherein the second substrate comprises at least one member selected from the group consisting of alumina, titania, zirconia, ceria, silicon carbide and mixtures thereof. 
     
     
       12. The catalyst system of  claim 1 , further comprising a delivery system configured to deliver a reductant. 
     
     
       13. The catalyst system of  claim 12 , wherein the reductant is a hydrocarbon. 
     
     
       14. The catalyst system of  claim 13 , wherein the hydrocarbon has an average carbon chain length in a range of about 2 carbon atoms to about 24 carbon atoms. 
     
     
       15. The catalyst system of  claim 12 , wherein the reductant is one or more of diesel, ultra-low sulfur diesel, ethanol, gasoline, and octane. 
     
     
       16. The catalyst system of  claim 12 , wherein the reductant is an oxygenated hydrocarbon. 
     
     
       17. The catalyst system of  claim 16 , wherein the reductant is ethanol. 
     
     
       18. The catalyst system of  claim 12 , wherein the reductant is diesel. 
     
     
       19. The catalyst system of  claim 12 , wherein the delivery system further comprises a co-reductant. 
     
     
       20. The catalyst system of  claim 19 , wherein the co-reductant is hydrogen.